Diuretics

What are they?
Diuretics are drugs that change your body's natural balance of fluids and salts (electrolytes) and can lead to dehydration. This loss of water can decrease an athlete's weight, helping him or her to compete in a lighter weight class, which many athletes prefer. Diuretics may also help athletes pass drug tests by diluting their urine and are sometimes referred to as a "masking" agent.

Risks
Diuretics taken at any dose, even medically recommended doses, predispose athletes to adverse effects such as:

Dehydration

Muscle cramps

Exhaustion

Dizziness

Fainting

Potassium deficiency

Heart arrhythmias

Drop in blood pressure

Loss of coordination and balance

Heatstroke

Death

Creatine

What is it?
Many athletes take nutritional supplements instead of or in addition to performance-enhancing drugs. Supplements are available over-the-counter as powders or pills.

The most popular supplement among athletes is probably creatine monohydrate. Creatine is a naturally occurring compound produced by your body that helps your muscles release energy.

Scientific research indicates that creatine may have some athletic benefit by producing small gains in short-term bursts of power. Creatine appears to help muscles make more adenosine triphosphate (ATP), which stores and transports energy in cells, and is used for quick bursts of activity, such as weightlifting or sprinting. There's no evidence, however, that creatine enhances performance in aerobic or endurance sports.

Your liver produces about 0.07 ounces (2 grams) of creatine each day. You also get creatine from the meat in your diet. Creatine is stored in your muscles, and levels are relatively easily maintained. Because your kidneys remove excess creatine, the value of supplements to someone who already has adequate muscle creatine content is questionable.

Risks
Supplements are considered food and not drugs by the FDA. This means supplement manufacturers are not required to conform to the same standards as drug manufacturers do. In some cases, supplements have been found to be contaminated with other substances, which may inadvertently lead to a positive test for performance-enhancing drugs.

Possible side effects of creatine that can decrease athletic performance include:

Stomach cramps

Muscle cramps

Nausea

Diarrhea

Weight gain

Weight gain is sought after by athletes who want to increase their size. But with prolonged creatine use, weight gain is more likely the result of water retention than an increase in muscle mass. Water is drawn into your muscle tissue, away from other parts of your body. This puts you at risk of dehydration.

High-dose creatine use may potentially damage your:

Kidneys

Liver

It appears safe for adults to use creatine at the doses recommended by manufacturers. But there are no studies investigating the long-term benefits and risks of creatine supplementation.

Stimulants

What are they?
Some athletes use stimulants to stimulate the central nervous system and increase heart rate and blood pressure.

Stimulants can:

Improve endurance

Reduce fatigue

Suppress appetite

Increase alertness and aggressiveness

Common stimulants include caffeine and amphetamines. Cold remedies often contain the stimulants ephedrine or pseudoephedrine hydrochloride. Energy drinks, which are popular among many athletes, often contain high doses of caffeine and other stimulants. The street drugs cocaine and methamphetamine also are stimulants.

Risks
Although stimulants can boost physical performance and promote aggressiveness on the field, they have side effects that can impair athletic performance.

Nervousness and irritability, which make it hard to concentrate on the game.

Insomnia, which can prevent an athlete from getting needed sleep.

Dehydration.

Heatstroke.

Addiction or tolerance, meaning that athletes need greater amounts to achieve the desired effect, so they'll take doses that are much higher than the intended medical dose.

Other side effects include:

Heart palpitations

Heart rhythm abnormalities

Weight loss

Tremors

Mild high blood pressure (hypertension)

Hallucinations

Convulsions

Stroke

Heart attack and other circulatory problems

The bottom line

Do performance-enhancing drugs boost performance? Some athletes may appear to achieve physical gains from such drugs, but at what cost? The long-term effects of performance-enhancing drugs haven't been rigorously studied. And short-term benefits are tempered by many risks. Not to mention that doping is prohibited by most sports organizations. No matter how you look at it, using performance-enhancing drugs is risky business.

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